A comprehensive protocol for manual segmentation of the medial temporal lobe structures

Area of Science:

• Neuroscience
• Neuroanatomy
• Medical Imaging

Background:

• The medial temporal lobe (MTL) is crucial for memory and emotion.
• Existing tracing protocols often focus on limited MTL subregions, hindering a holistic anatomical understanding.
• Accurate delineation of MTL structures is essential for neuroimaging research.

Purpose of the Study:

• To provide a comprehensive manual tracing protocol for all medial temporal lobe (MTL) subregions.
• To offer an integrative approach for localizing the amygdala, hippocampus, and associated parahippocampal regions.
• To serve as an accurate and intuitive guide for MTL anatomy.

Main Methods:

• Integration of information from existing tracing protocols, histological reports, and brain atlases.
• Inclusion of illustrative visual materials to guide manual tracing.
• Development of a protocol focusing on the complete set of MTL structures.

Main Results:

• A comprehensive and integrative protocol for manual tracing of the entire MTL.
• Clear localization of all MTL subregions, including amygdala, hippocampus, perirhinal, entorhinal, and parahippocampal cortex.
• Demonstration of the advantages over protocols focusing on isolated MTL areas.

Conclusions:

• The developed protocol enables accurate and convenient understanding of MTL anatomy.
• Highlights the importance of manual segmentation over automatic methods for precise ROI definition.
• Facilitates structural MRI, functional-structural colocalization, and fMRI analysis in various research groups.